MDL-38055 course: fixed double encoding of title properties

lib/navigationlib.php

@@ -2367,7 +2367,9 @@ class global_navigation extends navigation_node {
         $coursenode = $parent->add($coursename, $url, self::TYPE_COURSE, $shortname, $course->id);
         $coursenode->nodetype = self::NODETYPE_BRANCH;
         $coursenode->hidden = (!$course->visible);
-        $coursenode->title($fullname);
+        // We need to decode &'s here as they will have been added by format_string above and attributes will be encoded again
+        // later.
+        $coursenode->title(str_replace('&', '&', $fullname));
         if (!$forcegeneric) {
             $this->addedcourses[$course->id] = $coursenode;
         }